title: Measurement of free carnitine and acylcarnitines in plasma by HILIC-ESI-MS/MS without derivatization.
abstract: Measurement of carnitine and acylcarnitines in plasma is important in diagnosis of fatty acid β-oxidation disorders and organic acidemia. The usual method uses flow injection tandem mass spectrometry (FIA-MS/MS), which has limitations. A rapid and more accurate method was developed to be used for high-risk screening and diagnosis. Carnitine and acylcarnitines were separated by hydrophilic interaction liquid chromatography (HILIC) without derivatization and detected with a QTRAP MS/MS System. Total analysis time was 9.0min. The imprecision of within- and between-run were less than 6% and 17%, respectively. Recoveries were in the range of 85-110% at three concentrations. Some acylcarnitine isomers could be separated, such as dicarboxylic and hydroxyl acylcarnitines. The method could also separate interferent to avoid false positive results. 216 normal samples and 116 patient samples were detected with the validated method, and 49 patients were identified with fatty acid oxidation disorders or organic acidemias.
authors.affiliation: The Laboratory of Endocrinology and Metabolism, Guangzhou Women and Children's Medical Center, No. 9 Jinsui Road, Guangzhou, China.
authors.forename: Minzhi
authors.initials: M
authors.lastname: Peng
authors.forename: Li
authors.initials: L
authors.lastname: Liu
authors.forename: Minyan
authors.initials: M
authors.lastname: Jiang
authors.forename: Cuili
authors.initials: C
authors.lastname: Liang
authors.forename: Xiaoyuan
authors.initials: X
authors.lastname: Zhao
authors.forename: Yanna
authors.initials: Y
authors.lastname: Cai
authors.forename: Huiying
authors.initials: H
authors.lastname: Sheng
authors.forename: Zhiying
authors.initials: Z
authors.lastname: Ou
authors.forename: Hong
authors.initials: H
authors.lastname: Luo
mesh_terms: D002331:Carnitine / Q000031:analogs & derivatives* / Q000097:blood* / Q000302:isolation & purification; D002853:Chromatography, Liquid / Q000379:methods; D006801:Humans; D057927:Hydrophobic and Hydrophilic Interactions; D007536:Isomerism; D012680:Sensitivity and Specificity; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods; D053719:Tandem Mass Spectrometry / Q000379:methods*
chemical_list: C116917:acylcarnitine; D002331:Carnitine
keywords: 18-OH; AAPS; Acylcarnitine isomer; American Association of Pharmaceutical Scientists; BSA; C0; C10; C12; C14; C16; C16-OH; C16:1-OH; C18; C18:1-OH; C2; C3; C4; C4DC; C5; C5:1; C5DC; C6; C6-OH; C8; C8-OH; CE; CPDA; DP; EPI; ESI; FIA-MS/MS; Fatty acid β-oxidation disorders; HILIC; HPLC; IDA; IS; LC–MS/MS; MRM; Organic acidemia; PBS; QCs; acetylcarnitine; bovine serum albumin; butyrylcarnitine; carnitine; citrate phosphate dextrose adenine; collision energy; decanoylcarnitine; declustering potential; electrospray ion source; enhanced product ion monitoring; flow injection tandem mass spectrometry; glutarylcarnitine; hexanoylcarnitine; high performance liquid chromatography; hydrophilic interaction liquid chromatography; hydroxy hexanoylcarnitine; hydroxy octanoylcarnitine; hydroxy-hexadecanoylcarnitine; hydroxy-octadecanoylcarnitine; hydroxy-octadecenoylcarnitine; hydroxy-palmitoleoylcarnitine; information dependent acquisition; internal standard; isovalerylcarnitine; lauroylcarnitine; multiple reaction monitoring; myristoylcarnitine; octanoylcarnitine; palmitoylcarnitine; phosphate buffer solution; propionylcarnitine; quality control samples; stearoylcarnitine; succinylcarnitine and methylmalonylcarnitine; tiglylcarnitine